Principal Software Engineer London – Hybrid Up to £140k + bonus
We’re working with a profitable, engineering-led fintech that builds software used by investment firms to manage reporting, data, and client-facing outputs.
Their platform underpins core workflows for their clients – handling complex, highly tailored requirements across data processing, reporting logic, and content generation. They’re now at a key stage of growth: evolving the existing system while building out new products alongside it.
They’re looking for a Principal Engineer to take ownership of how that platform develops from here. This is a senior, hands-on position with real influence over both architecture and delivery.
You’ll be: Leading the evolution of a live, business-critical Python platform Designing and building new systems and features from the ground up Owning architectural decisions across backend services and cloud infrastructure Working closely with stakeholders to shape solutions, not just implement them Setting technical direction and raising engineering standards within a small team
What They’re Looking For: Strong Python experience (FastAPI, Django, Flask etc) Track record of owning or significantly evolving production systems Experience making architectural decisions and working across the full lifecycle Comfortable operating in a smaller, high-ownership environment Able to communicate effectively with both technical and non-technical stakeholders
Why It’s interesting: Ownership of a core platform and its future direction Worldwide travel insurance Top-tier Medical + Dental insurance Beautiful, modern office in Central London Profitable company with a clear growth roadmap…